Classical philosophy and Darwinian biology are far more compatible than is usually assumed. In fact, looking at either from the standpoint of the other can enrich and deepen our appreciation of both. From a Darwinian point of view, the theories of Plato and Aristotle deserve to be taken very seriously. From the classical point of view, Darwinian biology is much less reductionist than its enemies suppose.

Saturday, April 2, 2016

Late Night Thoughts on Being

We live at a moment of embarrassing
riches. I won’t try to catalog our
blessings, but I will point out one particular blessing. Someone who wants to think and knows how can
find a lot of new ways to think about interesting things, just a few key
strokes away. Three online journals deliver
bite sized brilliance for free: Aeon, This View of Life,
and Nautilus.
All three feature consistently provocative, thoughtful, well written,
articles that are easily accessible to anyone well-informed enough to be
interested.

I have been feasting on the third
tonight. Chip Rowe lists the “Top
10 Design Flaws in the Human Body.”
These design flaws count, in my view, as some of the strongest pieces of
evidence for human evolution. Take
number one, for example. The human
spine, with its double curve, puts a ridiculous amount of stress on the lower
back. My beagle’s spine, by contrast,
seems perfectly engineered: a curve that distributes weight evenly between two
sets of limbs. Of course, that was the
cost of freeing our forelimbs to do such tasks as checking our Facebook
pages. Rowe’s opening sentences express
what is marvelous about these new journals.

The Greeks were obsessed with the mathematically perfect body.
But unfortunately for anyone chasing that ideal, we were designed not by
Pygmalion, the mythical sculptor who carved a flawless woman, but by MacGyver.

Yes. The sculptor begins with a hunk of material but
designs from scratch. MacGyver has to
work with what he has and can exploit but is limited by the design already
present in whatever he can pull out of the crashed plane. Like MacGyver, natural selection must rig
solutions to present problems. If you
wanted to design a bipedal spine from scratch, maybe you could get perfection. If you have to start with a quadruped and
raise it off the ground, then compromises are inevitable.

William S. Burroughs, in his novel The Ticket That
Exploded, imagined that beneath a planetary surface, lies “a vast mineral
consciousness near absolute zero thinking in slow formations of crystal.”

As it happens, I have been
reading William S. Burroughs lately‑his letters and his novels Naked Lunch
(like Moby Dick, an almost impossible read) and Junky (so good you won’t need
heroin). Laughlin thinks Burroughs is
onto something. Consider the speed of
thought.

The speed of neural transmissions is about 300 kilometers per
hour, implying that the signal crossing time in a human brain is about 1
millisecond. A human lifetime, then, comprises 2 trillion message-crossing
times (and each crossing time is effectively amplified by rich, massively
parallelized computational structuring). If both our brains and our neurons
were 10 times bigger, and our lifespans and neural signaling speeds were
unchanged, we’d have 10 times fewer thoughts during our lifetimes.

This explains what happened to
the Amazing Colossal Man.

If our brains grew enormously to say, the size of our solar
system, and featured speed-of-light signaling, the same number of message
crossings would require more than the entire current age of the universe,
leaving no time for evolution to work its course.

Maybe our brain size, like Baby
Bear’s porridge, is just right: bigger than a chimp but small enough to
efficiently cohere.

It may be that human brains
specifically and living organisms generally must occupy a particular niche in the
scale of physics. Allison Eck puts the
general point in “How
Do You Say “Life” in Physics?”

The arrow of time points in the direction of disorder. The
arrow of life, however, points the opposite way. From a simple, dull seed grows
an intricately structured flower, and from the lifeless Earth, forests and
jungles. How is it that the rules governing those atoms we call “life” could be
so drastically different from those that govern the rest of the atoms in the
universe?

In 1944, physicist Erwin Schrödinger tackled this question in
a little book called What is Life?. He recognized that living
organisms, unlike a gas in a box, are open systems. That is, they admit the
transfer of energy between themselves and a larger environment. Even as life
maintains its internal order, its loss of heat to the environment allows the
universe to experience an overall increase in entropy (or disorder) in
accordance with the second law.

I was insufficiently amazed by Erwin
Schrödinger’s book when first I read it many years ago.

Schrödinger pointed to a second mystery. The mechanism that
gives rise to the arrow of time, he said, cannot be the same mechanism that
gives rise to the arrow of life. Time’s arrow arises from the statistics of
large numbers—when you have enough atoms milling about, there are simply so
many more disordered configurations than ordered ones that the chance of their
stumbling into a more ordered state is nil. But when it comes to life, order
and irreversibility must reign even at the microscopic scale, with far fewer
atoms in play. At this scale, atoms don’t come in large enough numbers for
their statistics to yield regularities like the second law. A nucleotide—the
building block of RNA and DNA, the basic components of life—is, for example,
made of just 30 atoms. And yet, Schrödinger noted, genetic codes hold up
impossibly well, sometimes over millions of generations, “with a durability or
permanence that borders upon the miraculous.”

Living organisms are dependent
upon physical processes that are small enough that they are not subject to the laws
of averages. This sequestering from
larger physical processes is the first sequestering. Before life could begin, there had to be a
small space for it to begin. Once it
does begin, it sequesters itself in successively more effective ways.

But what can account for the “arrow
of life”, that is, the direction of organic processes towards greater order
(less entropy)? Well, I guess I’ll blog
on that tomorrow.